On 10:57 Fri 11 Jan , sahlot arvind wrote: > Hi All, > > I just started learning Linux Virtual Memory Management Subsystem. > I see the memory is divided into three zones. Comments in file mm/mmzone.h > > /* > * ZONE_DMA < 16 MB ISA DMA capable memory > * ZONE_NORMAL 16-896 MB direct mapped by the kernel > * ZONE_HIGHMEM > 896 MB only page cache and user processes > */ > > Here second comment (ZONE_NORMAL) says that it is directly mapped by kernel. > > Could anybody please tell me what does direct mean here? > Does this mean Physical address = Virtual Address??? Yes, it that sense. But in 386 the mapping starts at the virtual address 3GB (or 2GB, depending on your memory split configuration). The virtual addresses 0-3GB (or 2GB) are for the userspace. -Michi -- programing a layer 3+4 network protocol for mesh networks see http://michaelblizek.homelinux.net -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
